Inhibitory action of levocetirizine on the production of eosinophil chemoattractants RANTES and eotaxin in vitro and in vivo.

Eosinophils are well known to play essential roles in the development and maintenance of allergic diseases. However, the influence of histamine H1 receptor antagonists on eosinophil functions, especially chemokine production, are not well-defined. Therefore, in the present study, we examined the influence of histamine H1 receptor antagonist on chemokine production by eosinophils through the use of levocetirizine in vitro and in vivo. Eosinophils prepared from mice were stimulated with specific antigens in the presence of different concentrations of levocetirizine. After 24 h, regulated on activation normal T cell expressed and secreted (RANTES) and eotaxin levels in culture supernatants were measured by enzyme-linked immunosorbent assay (ELISA). Patients with Japanese cedar pollinosis were treated with 5 mg levocetirizine once a day for four weeks during the pollen season (February 2012 to April 2012). RANTES and eotaxin levels in nasal secretions were also examined by ELISA. The addition of levocetirizine to eosinophil cultures caused a dose-dependent decrease in the ability of cells to produce RANTES and eotaxin in response to antigen stimulation, and the minimum concentration that caused a significant decrease was 0.05 µM. Although cetirizine also exerted suppressive effects on the production of RANTES and eotaxin by eosinophils, the minimum concentration that caused significant suppression was 0.15 µM, which was three-times higher than that of levocetirizine. Oral administration of levocetirizine for four weeks also reduced RANTES and eotaxin levels in nasal secretions from patients with pollinosis, along with attenuation of clinical symptoms. The ability of levocetirizine to reduce RANTES and eotaxin levels may account, at least in part, for the clinical efficacy of the agent for allergic disorders, including allergic rhinitis.

Crystallization and preliminary crystallographic studies of PotA, a membrane-associated ATPase of the spermidine-preferential uptake system in Thermotoga maritima.

A membrane-associated ATPase, PotA, is a component of the spermidine-preferential uptake system in prokaryotes that plays an important role in normal cell growth by regulating the cellular polyamine concentration. No three-dimensional structures of membrane-associated ATPases in polyamine-uptake systems have been determined to date. Here, the crystallization and preliminary X-ray diffraction analysis of PotA from Thermotoga maritima are reported. Diffraction data were collected and processed to 2.7 Šresolution from both native and selenomethionine-labelled crystals. Preliminary crystallographic analysis revealed that the crystals belonged to the hexagonal space group P3112 (or P3212), with unit-cell parameters a=b=88.9, c=221.2 Å, α=90, ß=90, γ=120°, indicating that a dimer was present in the asymmetric unit.

Suppression of osteopontin functions by levocetirizine, a histamine H1 receptor antagonist, in vitro.

OBJECTIVES: Osteopontin (OPN), a multifunctional glycoprotein secreted from a wide variety of cells after inflammatory stimulation, is well accepted to contribute to the development of allergic diseases. However, the influence of histamine H1 receptor antagonists (antihistamines) on OPN functions is not well understood. The present study was undertaken to examine the influence of antihistamines on OPN functions in vitro. METHODS: Human nasal epithelial cells (5 × 10(5) cells) were stimulated with 250 ng/mL OPN in the presence of either desloratadine (DL), fexofenadine (FEX), or levocetirizine (LCT). The levels of OPN, GM-CSF, Eotaxin, and RANTES in 24 h culture supernatants were examined by ELISA. The influence of LCT on mRNA expression and transcription factor activation in cells were also examined by real-time RT-PCR and ELISA, respectively. KEY FINDINGS: The antihistamines examined significantly suppressed the production of GM-CSF, Eotaxin, and RANTES from cells after OPN stimulation. LCT also exhibited the suppression of mRNA expression for chemokines and transcription factor, NF- κ B and AP-1, activation, which were increased by the stimulation of cells with OPN. CONCLUSIONS: The suppressive activity of LCT on OPN functions on nasal epithelial cells may be responsible for the attenuating effect of the agent on allergic diseases.

Enhancement of clara cell 10-kD protein (CC10) production from nasal epithelial cells by fexofenadine hydrochloride.

BACKGROUND: Clara cell 10-kD protein (CC10) is well known to be an immuno-suppressive protein secreted from airway epithelial cells after inflammatory stimulation and is involved in the development of allergic disorders. Although histamine H1 receptor antagonists are used for the treatment of allergic disorders, the influence of the agents on CC10 production is not well understood. In the present study, we examined the influence of a histamine H1 receptor antagonist, fexofenadine hydrochloride (FEX) on CC10 production in vitro and in vivo. METHODS: Nasal epithelial cells (5 x 10(6) cells/ml) were stimulated with 20 ng/ml TNF-alpha in the presence of various concentrations of FEX for 24 hours. CC10 levels in culture supernatants were examined by ELISA. Patients with Japanese cedar pollinosis were treated orally with FEX twice a day at a single dose of 60 mg for two weeks during Japanese cedar pollen season (February 2011 to April 2011). CC10 levels in nasal secretions were also examined by ELISA. RESULTS: The addition of FEX into cell cultures caused increase in CC10 production induced by TNF-alpha stimulation, and the minimum concentration that caused significant increase was 200 ng/ml. Oral administration of FEX also increased CC10 levels in nasal secretions from pollinosis patients along with attenuation of clinical symptoms. CONCLUSION: The ability of FEX to enhance CC10 production may account, at least in part, for the clinical efficacy of the agent in allergic disorders, including allergic rhinitis.

Typical carcinoid tumor arising in the nose and paranasal sinuses--case report.

Carcinoid tumors arise from neuroendocrine cells, many of which are present in the digestive tract and lungs. There have been few reports of carcinoid tumors occurring in the nose and paranasal sinus area, and they are very rare. We encountered a patient with a carcinoid tumor that arose in the nose and paranasal sinuses, and we report the case with a review of the literature. The patient was a 75-year-old woman who began to experience right-sided nasal obstruction, and when her nose began to bleed on the right-side she was examined in our department. A tumor lesion that easily bled and had filled the right nasal cavity was observed. CT revealed a mass lesion with a marked contrast enhancement in the right nasal cavity, ethmoid sinus, and sphenoid sinus, and MRI showed numerous flow voids in the interior that seemed to be tumor blood vessels. The tumor was excised through a lateral rhinotomy. The histopathological diagnosis was a carcinoid tumor. Tumor recurrence was subsequently detected in the vicinity of the opening of the sphenoid sinus, and because the tumor was tending to grow larger, the tumor was resected. The patient has been followed up in the outpatient clinic, recurrence-free.

Glucocorticoid receptor immunoreactivity of eosinophils in nasal polyps.

CONCLUSION: The higher level of glucocorticoid receptor (GR) expression in cases of chronic sinusitis with bronchial asthma or allergic rhinitis suggests that glucocorticoids may exert a greater influence on eosinophils, thereby making them more effective in the treatment of polyps or chronic sinusitis. OBJECTIVES: The GR immunoreactivity of eosinophils in nasal polyps was investigated to elucidate the mechanism by which glucocorticoids interact with eosinophils. MATERIALS AND METHODS: Nasal polyp specimens were divided into 3 groups: 7 patients with chronic sinusitis alone (CS only group), 12 patients with chronic sinusitis complicated by perennial allergic rhinitis (CS/AR group), and 6 patients with chronic sinusitis complicated by bronchial asthma except for aspirin-induced asthma (CS/asthma group). Immunofluorescent staining with an anti-GR polyclonal antibody and anti-major basic protein (MBP) monoclonal antibody was used. RESULTS: The total number of MBP+ cells, GR+ cells, and MBP+/GR+ cells in the CS/asthma group was significantly higher than that in the other two groups. The total number of these cells in the CS/AR group was also higher than that in the CS only group The ratio of MBP+/GR+ cells to GR+ cells was highest in the CS/asthma group. The ratio of MBP+/GR+ cells to MBP+ cells in the CS only group was lower than those in the other two groups.

Evidence for passing down of postnasal drip into respiratory organs.

UNLABELLED: Postnasal drip is believed to be one of the main sources of serious respiratory diseases, such as sinobronchial syndrome. However, there is little direct evidence showing that postnasal drip flows into the trachea and results in the development of inflammatory responses in the lower airway. In the present study, whether postnasal drip entered the respiratory organs and whether material in the trachea moved toward the lungs and the digestive organs were examined by using an experimental model with mice. MATERIALS AND METHODS: In the first set of experiments, 1.0 microL of 51Cr-labeled pseudo-postnasal drip in a normal saline or a glycerin solution was instilled into the nasal cavity of male ICR mice anesthetized with sodium barbital by intraperitoneal injection. In the second set of experiments, the destination of 51Cr-labeled red blood cells (RBCs) after intratracheal instillation was examined in the anesthetized mice. The lungs, the stomach and the intestines were removed from mice killed under anesthesia at various intervals after instillation, and measured for radioactivity. RESULTS: When glycerin solution containing 51Cr (but not normal saline) was instilled in mice, the presence of much higher levels of 51Cr was observed in the lungs. Although the presence of high levels of 51Cr-labeled RBCs was observed in the lungs one hour after instillation radioactivity in the lungs gradually decreased as time went by. On the other hand, radioactivity in the digestive organs gradually increased and peaked three hours after instillation with 51Cr-labeled RBC. CONCLUSION: These results suggest that thicker viscous postnasal drip can flow into the respiratory organs when the host is asleep. In addition, postnasal drip which flows into the trachea can move gradually to the oral side by mucociliary transportation of the tracheal mucosa and thus be swallowed.

Influence of epinastine hydrochloride, an H1-receptor antagonist, on the function of mite allergen-pulsed murine bone marrow-derived dendritic cells in vitro and in vivo.

There is established concept that dendritic cells (DCs) play essential roles in the development of allergic immune responses. However, the influence of H(1) receptor antagonists on DC functions is not well defined. The aim of the present study was to examine the effect of epinastine hydrochloride (EP), the most notable histamine H(1) receptor antagonists in Japan, on Dermatophagoides farinae (Der f)-pulsed mouse bone marrow-derived DCs in vitro and in vivo. EP at more than 25 ng/mL could significantly inhibit the production of IL-6, TNF-alpha and IL-10 from Der f-pulsed DCs, which was increased by Der f challenge in vitro. On the other hand, EP increased the ability of Der f-pulsed DCs to produce IL-12. Intranasal instillation of Der f-pulsed DCs resulted in nasal eosinophilia associated with a significant increase in IL-5 levels in nasal lavage fluids. Der f-pulsed and EP-treated DCs significantly inhibited nasal eosinophila and reduced IL-5. These results indicate that EP inhibits the development of Th2 immune responses through the modulation of DC functions and results in favorable modification of clinical status of allergic diseases.

Suppressive activity of epinastine hydrochloride on eosinophil activation in vitro.

The influence of a histamine H1 receptor antagonist, epinastine hydrochloride (EP), on eosinophil functions was examined in vitro and in vivo. The first set of experiments was undertaken to examine whether EP could suppress eosinophilia and IgE hyperproduction induced by Mesocestoides cortii infection in BALB/c mice. The number of peripheral blood eosinophils and levels of IgE were examined 21 days after infection. Oral administration of EP at a daily dose of 0.3 mg/kg, which is the recommended human therapeutic dose, for 21 days was not able to suppress either peripheral blood eosinophilia or IgE hyperproduction, which was observed in mice infected with M. cortii. The second part of the experiment was designed to examine the influence of EP on eosinophil activation induced by stem cell factor (SCF) stimulation in vitro. Eosinophils were obtained from M. cortii-infected mice and stimulated with SCF in the presence of different concentrations of EP for 24 h. The addition of EP into cell cultures suppressed eosinophil activation induced by SCF stimulation as assessed by measuring the contents of acronym for Regulated upon Activation, Normal T cell Expressed and presumably Secreted (RANTES), macrophage inflammatory protein-1beta (MIP-1beta) and leukotriene C4 (LTC4) levels in culture supernatants. The minimum concentration of EP which caused significant suppression of factor productions was 25 ng/ml, which is similar to the concentration in plasma after oral administration of the therapeutic dose in humans. These results may suggest that EP exerts inhibitory effects on eosinophil activation and results in favorable modification of the clinical status of allergic patients.

Suppressive activity of tiotropium bromide on matrix metalloproteinase production from lung fibroblasts in vitro.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterized by airway remodeling with an accumulation of inflammatory cells. There is also increasing evidence that metalloproteinases (MMPs) may contribute to the pathogenesis of COPD, but the influence of agents that used for the treatment of COPD is not well understood. OBJECTIVE: We evaluated whether tiotropium bromide hydrate (TBH), a M3 muscarinic receptor antagonist, could inhibit MMP production from lung fibroblasts (LFs) in response to tumor necrosis factor (TNF)-alpha stimulation. METHODS: LFs were established from normal lung tissues taken from patients with lung tumors. LFs (5 x 10(5) cells/ml) were stimulated with TNF-alpha in the presence of various concentrations of TBH. After 24 h, culture supernatants were obtained and assayed for the levels of MMPs and tissue inhibitor of metalloproteinases (TIMPs) by ELISA. The influence of TBH on mRNA expression of MMPs and TIMPs in 4h-cultured cells was also examined by real-time RT-PCR. Furthermore, nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) in LFs treated with TBH for 4h was examined by ELISA. RESULTS: TBH at more than 15 pg/ml inhibited the production of MMP-2 from LFs after TNF-alpha stimulation, whereas TIMP-1 and TIMP-2 production was scarcely affected by TBH through the suppression of both mRNA expression and transcription factor, NF-kappaB, activation in LFs induced by TNF-alpha stimulation. CONCLUSION: These results suggest that the attenuating effect of TBH on MMP-2 production from LFs induced by inflammatory stimulation may be additional beneficial therapeutic effects not directly relating to its bronchodilatory effects.

Modulation of eosinophil survival by epinastine hydrochloride, an H1 receptor antagonist, in vitro.

The influence of epinastine hydrochloride (EP) on eosinophil survival was examined by an in vitro cell culture technique. Nasal epithelial cells (NECs) were stimulated with 25 ng/ml TNF-alpha in the presence of EP (10 to 30 ng/ml). After 24 h, the culture supernatants were obtained and used as conditioned media of NECs (CM). Eosinophils (1 x 10(3) cells/ml) prepared from healthy human peripheral blood were incubated with 25% CM and eosinophil survival was assessed by trypan blue dye exclusion test 48 h later. CM prepared from NEC cultures pre-treated with TNF-alpha and EP caused a decrease in eosinophil survival as compared with that from NEC cells pre-treated with TNF-alpha alone. The minimum concentration of EP that caused a significant decrease in eosinophil survival was 25 ng/ml. The addition of EP into eosinophil cultures did not cause inhibition of eosinophil survival, which was prolonged by stimulation with granulocyte-macrophage colony-stimulating factor (GM-CSF), even when 40 ng/ml EP was added to cell cultures. We then examined the levels of GM-CSF in CM by ELISA. Treatment of NECs with EP at more than 25 ng/ml, reduced the ability of NECs to produce GM-CSF in response to TNF-alpha stimulation. These results may suggest that EP suppresses eosinophil survival through the suppression of GM-CSF production from NECs induced by inflammatory stimulation and that this suppressive effect contributes, in part, to the therapeutic mode of action of EP on allergic diseases.

Suppressive activity of fexofenadine hydrochloride on nitric oxide production in-vitro and in-vivo.

The aim of this study was to examine the effect of fexofenadine hydrochloride (FEX), a histamine H1-receptor antagonist, on nitric oxide (NO) production in-vitro and in-vivo. Nasal fibroblasts (5 x 10(5) cells per mL) were stimulated with 25 ng mL(-1) tumour necrosis factor-alpha in the presence of various concentrations of FEX. NO levels in 24-h-culture supernatants were measured by the Griess method and levels of inducible nitric oxide synthase (iNOS) mRNA levels in 12-h-cultured cells were measured by ELISA. FEX at more than 0.5 microg mL(-1) suppressed NO production from fibroblasts by inhibiting expression of iNOS mRNA. We also examined whether FEX could suppress NO production induced by lipopolysaccharide (LPS) stimulation in-vivo. BALB/c mice were treated with 5.0 mg kg(-1) LPS i.p. after daily oral doses of FEX, 1.0 mg kg(-1), for 1-3 weeks. Plasma was obtained 6 h later and NO levels measured by the Griess method. Expression of iNOS mRNA in lung tissues was measured by ELISA 6 h after LPS injection. Oral administration of FEX for 2 and 3 weeks, but not 1 week, significantly suppressed NO levels in plasma through the inhibition of iNOS mRNA expression, which were enhanced by LPS stimulation. These results suggest that the attenuating effect of FEX on NO production may be of therapeutic benefit in allergic diseases.

Suppressive effect of fluticasone propionate on MMP expression in the nasal mucosa of allergic rhinitis patients in vivo.

The effects of intranasal corticosteroids on matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of metalloproteinases (TIMPs)) in the nasal mucosa of patients with allergic rhinitis (AR) are not known. Nasal mucosa biopsy specimens were obtained from AR patients, with or without the administration of fluticasone propionate (FP) nose drops, and from healthy volunteers as controls. The specimens were analyzed by immuno-histochemistry and ELISA for MMP-2, MMP-9, TIMP-1 and TIMP-2. The MMP-9 levels in nasal mucosa extracts in the AR patients were significantly higher than in the controls. A significant suppressive effect of FP on the MMP-9 levels was shown. The control subjects showed no MMP- or TIMP-positive cells, whereas such positive cells were clearly present in the AR patients. No MMP- or TIMP-positive cells were detected after topical application of FP. These results suggest that the suppressive effect of FP on MMP expression is, in part, responsible for its clinical efficacy in AR.

Epinastine hydrochloride antagonism against interleukin-4-mediated T cell cytokine imbalance in vitro.

BACKGROUND: Interleukin (IL)-4 is well accepted to be a cytokine that plays many roles in the regulation of immune responses. Although the primary pharmacological target of antihistamines has been regarded as the histamine H1 receptor, there is little information about the influence of antihistamines on IL-4-mediated immune responses. The present study was undertaken to examine whether H1 receptor antagonists could modulate IL-4-mediated immune responses in vitro. METHODS: CD4+ T cells from normal human peripheral blood (1 x 10(6) cells/ml) were incubated with various concentrations of epinastine hydrochloride (EP) or chlorpheniramine (CH) for 30 min and then stimulated with 10.0 ng/ml IL-4. After 24 h, culture supernatants were collected and assayed for IL-5, IL-6, IL-13 and interferon-gamma by ELISA. The influence of EP on transcription factor activation and mRNA expression for cytokines was also examined. RESULTS: Addition of EP into cell cultures at more than 20.0 ng/ml significantly suppressed the production of IL-5, IL-6 and IL-13, which were increased by IL-4 stimulation. EP at more than 20.0 ng/ml also suppresses nuclear factor-kappaB activation, signal transducers and activators of transcription 6 phosphorylation and mRNA expression, which were upregulated by IL-4 stimulation. However, the ability of CD4+ T cells to produce interferon-gamma was decreased by IL-4 stimulation, which was dramatically restored by treatment with EP at more than 15.0 ng/ml. On the other hand, CH, a first-generation H1 receptor antagonist, could not inhibit cytokine production from CD4+ T cells in response to IL-4 stimulation, even when 90.0 ng/ml of the agent was added to cell cultures. CONCLUSION: The present results strongly suggest that EP, a second-generation H1 receptor antagonist, interferes with IL-4-activated signaling in CD4+ T cells and results in favorable modification of the allergic disease state or conditions.

Effect of tranilast on matrix metalloproteinase production from neutrophils in-vitro.

Tranilast is an anti-allergic agent that blocks the release of chemical mediators, such as histamine and leukotrienes from mast cells, and has been reported to suppress keloid and hypertrophic scar formation. Since matrix metalloproteinases (MMPs) play an essential role in tissue remodelling, this study was undertaken to determine whether tranilast suppresses MMP production from neutrophils after lipopolysaccharide (LPS) stimulation in-vitro. Neutrophils from five healthy donors (1 x 10(5) cells/mL) were stimulated with 1.0 microg mL(-1) LPS in the presence or absence of various concentrations of tranilast for 24 h. MMP-7, MMP-8, MMP-9 and tissue inhibitor of metalloproteinase (TIMP)-1 levels in the culture supernatants were assayed by ELISA. In addition, the influence of tranilast on MMP mRNA expression and transcriptional factor activation in cells cultured for 12 h and 4 h was also evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Tranilast inhibited MMP and TIMP-1 production from neutrophils when cells were treated with the agent at more than 5.0 x 10(-5) M. It also suppressed MMP mRNA expression and transcriptional factor activation induced in neutrophils by LPS stimulation. The results suggest that tranilast inhibits the formation of keloid scarring through the suppression of factors such as MMPs and TIMP, which are essential for tissue remodelling, from inflammatory cells.

Suppressive activity of vitamin D3 on matrix metalloproteinase production from cholesteatoma keratinocytes in vitro.

There is much evidence that degradation of the extracellular matrix is essential for the development of cholesteatomas and that this is induced by activation of matrix metalloproteinases (MMPs). Vitamin D3 (VD3) has several well-recognised biological activities, including suppression of MMP production. The present study, therefore, was undertaken to examine whether VD3 could suppress MMP production from cholesteatoma keratinocytes in vitro. Keratinocytes (2.5 x 10(5) cells/mL) induced from cholesteatoma tissue specimens were cultured with various concentrations of VD3. After one hour, lipopolysaccharide was added to the cell cultures at 100 mug/mL. The culture supernatants were then collected and assayed for MMP-1 and MMP-3 by ELISA. We also used ELISA to measure the levels of both TIMP (tissue inhibitor of metalloproteinase)-1 and TIMP-2 in culture supernatants. Addition of VD3 into keratinocyte cultures caused the suppression of MMP and TIMP production, which was increased by LPS stimulation. This was dose-dependent. The present results showing the suppressive activity of VD3 on the production of MMPs, which are responsible for tissue remodeling, strongly suggest that VD3 would be a good candidate for an agent in the medical treatment of, or prophylaxis for, cholesteatomas.

Suppressive activity of epinastine hydrochloride on TARC production from human peripheral blood CD4+ T cells in-vitro.

Thymus- and activation-regulated chemokine (TARC) is an important molecule in the development and maintenance of allergic diseases. However, there is little information about the influence of anti-allergic agents on TARC production. The aim of this study is to examine the influence of epinastine hydrochloride, an H1-receptor antagonist, on TARC production from human peripheral blood CD4+ T cells using an in-vitro cell culture technique. CD4+ T cells prepared from healthy subjects were cultured in wells coated with a combination of OKT3 and anti-CD28 monoclonal antibody in the presence or absence of epinastine HCl for 24 h. The cells were also stimulated with interleukin (IL)-4 in a similar manner. Levels of TARC and IL-4 in culture supernatants were examined by ELISA. The addition of epinastine HCl exerted a dose-dependent suppressive effect on the production of both TARC and IL-4 from CD4+ T cells under co-stimulatory molecule stimulation. The minimum concentration of the agent showing a significant suppressive effect on TARC and IL-4 production was 5.0 microM and 2.5 microM, respectively. Epinastine HCl also suppressed the ability of cells to produce TARC in response to IL-4 stimulation, when the agent was added to cell cultures at more than 2.5 microM. It was concluded that this inhibitory action of epinastine HCl may be partially responsible for epinastine's attenuating effect on allergic diseases.

Suppression of matrix metalloproteinase production from nasal fibroblasts by fluticasone propionate in vitro.

OBJECTIVE: To examine the influence of fluticasone propionate (FP) on matrix metalloproteinase (MMP) production from nasal polyp fibroblasts in vitro. MATERIAL AND METHODS: Fibroblasts derived from five nasal polyps were stimulated with tumor necrosis factor (TNF)-alpha in the presence of various concentrations of FP. The influence of FP on MMP production was assessed by examining the levels of MMP-2 and -9 in culture supernatants using ELISA. We also examined the influence of FP on MMP mRNA expression using reverse transcriptase polymerase chain reaction. RESULTS: The addition of FP caused significant suppression of MMP-2 and -9 production from nasal polyp fibroblasts in response to TNF-alpha stimulation. MMP mRNA expression was also suppressed by the addition of FP to cell cultures. The minimum concentration of the agent required to cause suppression was 10(-5) M. CONCLUSION: These results suggest that the inhibitory action of FP on tissue remodeling may underlie the clinical efficacy of corticosteroids in nasal polyposis.

Suppressive activity of fexofenadine hydrochloride on the production of eosinophil chemoattractants from human nasal fibroblasts in vitro.

The influence of fexofenadine hydrochloride (FEX; CAS 138452-21-8) on the production of eosinophil chemoattractants, RANTES and eotaxin, from nasal polyp fibroblasts (NPFs) was examined in vitro. Seventh to tenth generation NPFs were cultured with or without 1 microg/ml lipopolysaccharide (LPS) in the presence of various concentrations of FEX. After 24 h, the culture supernatants were obtained and assayed for eosinophil chemoattractants by enzyme-linked immunosorbent assay (ELISA). FEX at a dose of more than 250 ng/ml (but not 100 ng/ml) inhibited RANTES and eotaxin production in response to LPS stimulation, when the agent was added at starting of cell cultures. FEX also showed suppressive effect on RANTES and eotaxin production from NPFs after stimulation with tumor necrosis factor alpha (TNF-alpha). However, the addition of FEX at 12 h after culture could not inhibit factor production. The influence of FEX on messenger RNA (mRNA) expression in NPFs was then examined. The addition of FEX at 100 ng/ml scarcely affected the expression of RANTES and eotaxin mRNA. On the other hand, 250 ng/ ml of FEX significantly inhibited these mRNA expressions that were enhanced by LPS stimulation.

Suppressive activity of fexofenadine hydrochloride on thymus- and activation-regulated chemokine production from human peripheral blood leukocytes in response to antigenic stimulation in vitro.

BACKGROUND: Thymus- and activation-regulated chemokine (TARC) is accepted as being an important molecule in the development and maintenance of allergic diseases. However, there is little information about the influence of antiallergic agents on TARC production after allergen challenge. The aim of this study is to examine the influence of fexofenadine hydrochloride (FEX), an H1-receptor antagonist, on TARC production from human peripheral blood leukocytes (PBL) using an in vitro cell culture technique. METHODS: PBL prepared from donors with pollinosis were cultured with either Japanese cedar pollen allergen, Cry j 1, or interleukin (IL)-4 in the presence of various doses of FEX for 6 days. Levels of TARC and the T cell cytokines IL-4 and interferon (IFN)-gamma in culture supernatants were examined by ELISA. RESULTS: FEX did not affect PBL proliferation induced by Cry j 1 stimulation, even when 500 ng/ml of the agent, twice the therapeutic blood levels, was added to cell cultures as assessed by measuring 3H-thymidine incorporation into DNA. On the other hand, FEX at 250 ng/ml (but not 125 ng/ml), similar to therapeutic blood levels, significantly inhibited the ability of PBL to produce IL-4 (but not IFN-gamma), which was enhanced by Cry j 1 stimulation. FEX at concentrations of more than 250 ng/ml also exerted a suppressive effect on TARC production from PBL in response to Cry j 1 and IL-4 stimulation in vitro. CONCLUSION: This inhibitory action of FEX may be partially responsible for the attenuating effect of the agent on allergic diseases.